tea2029c, Aplikacje data
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TEA2029C
COLOR TV SCANNING AND POWER SUPPLY PROCESSOR
.
CERAMIC 500kHz RESONATOR FRE-
QUENCY REFERENCE
DESCRIPTION
The TEA2029C is a complete (horizontal and ver-
tical) deflection processor with secondary to pri-
mary SMPS control for color TV sets.
.
NO LINE AND FRAME OSCILLATOR AD-
JUSTMENT
.
DUAL PLL FOR LINE DEFLECTION
.
HIGH PERFORMANCE SYNCHRONIZATION
.
SUPER SANDCASTLE OUTPUT
.
VIDEO IDENTIFICATION CIRCUIT
.
AUTOMATIC 50/60Hz STANDARD IDENTIFI-
CATION
.
EXCELLENT INTERLACING CONTROL
.
SPECIAL PATENTED FRAME SYNCHRO DE-
VICE FOR VCR OPERATION
.
FRAME SAW-TOOTH GENERATOR
.
FRAME PHASE MODULATOR FOR THYRIS-
TOR
SMPS CONTROL
.
SYNCHRONIZATION WITH HORIZONTAL
DEFLECTION
DIP28
(Plastic Package)
.
SECURITY CIRCUIT AND START UP PROC-
ESSOR
ORDER CODE :
TEA2029C
.
OUTPUT PULSES ARE SENT TO THE PRI-
MARY SMPS IC (TEA2261) THROUGH A
LOW COST TRANSFORMER
PIN CONNECTIONS
+ INPUT FRAME AMPLIFIER
- INPUT FRAME AMPLIFIER
1
2
3
4
5
6
7
8
9
10
28
27
26
SAFETY INPUT
VIDEO INPUT
FRAME SAW-TOOTH OUTPUT
FRAME OUTPUT
FRAME RAMP GENERATOR
GROUND POWER
HORIZONTAL SYNCHRO CAPACITOR (tip level)
25
VIDEO IDENTIFICATION CAPACITOR
24
23
22
21
MUTING +50/60Hz IDENTIFICATION OUTPUT
V.C.R. INPUT
SWITCH MODE POWER SUPPLY OUTPUT
PHASE COMPARATOR
j
1 CAPACITOR
V
CC
GROUND SUBSTRAT
S.M.P.S. INPUT REGULATION
HORIZONTAL OUTPUT
20
19
18
17
16
15
A.G.C. KEY PULSE OUTPUT
V.C.O. INTPUT
SUPER SANDCASTLE OUTPUT
11
12
V.C.O. OUTPUT
HORIZONTAL FLY-BACK INPUT
HORIZONTAL SAW-TOOTH
CURRENT REFERENCE
V.C.O. 90
°
REFERENCE
13
14
PHASE COMPARATOR
j
2 CAPACITOR
STARTING AND SAFETY CAPACITOR
August 1993
1/9
DEFLECTION
.
ERROR AMPLIFIER AND PHASE MODULA-
TOR
50/60Hz
MUTING OUTPUT
VCR SWITCHING
INPUT
AGC
OUTPUT
503kHz
SUBSTRAT
GROUND
25
24
23
22
21
20
19
18
TEA2029C
H. SYNC
SUBST
26
HORIZONTAL
SYNCHRO
AND FRAME
SYNCHRO
VCR
INPUT
j
1 DET
AGC
KEY PULSE
17
27
VCO 500kHZ
VIDEO
IDENTIFICATION
j
1 INHIBITION TIME
CONSTANT SWITCHING
VIDEO INPUT
SAFETY
INPUT
j
2
16
2
m
s
CONSTANT
PULSE WIDTH
26
28
FRAME TIMING
IDENTIFICATION LOGIC
HORIZONTAL
LOGIC TIMING
m
s
V
R
1.26V
15
V
CC
50/60Hz
REFERENCE
CURRENT
VOLTAGE
3.3k
W
V
R
1.26V
SWITCH ON/OFF
SAFETY CIRCUIT
14
1
2
FRAME ERROR
AMPLIFIER
SAFETY
LOGIC
H. SAWTOOTH
GENERATOR
13
FRAME
SAWTOOTH
OUTPUT
50/60
Hz
SOFT STARTING
CIRCUIT
3
INHIB.
SUPER
SANDCASTLE
H. OUTPUT
H. INHIBIT
FRAME
OUTPUT
12
FRAME
SAWTOOTH
OUTPUT
HORIZONTAL
FLYBACK
INPUT
S.M.P.S.
FRAME
PHASE
MODULAT.
S.M.P.S.
OUTPUT
j
MODULAT.
V
R
1.26V
4
5
6
7
8
9
10
11
V
CC
S SC OUTPUT
POWER
GROUND
HORIZONTAL
OUTPUT
FRAME
SAWTOOTH
2029C-02.EPS
TEA2029C
GENERAL DESCRIPTION
This integrated circuit uses I
2
L bipolar technology
and combines analog signal processing with digital
processing.
Timing signals are obtained from a voltage-control-
led oscillator (VCO) operatingat 500KHz by means
of a cheap ceramic resonator. This avoids the
frequency adjustment normally required with line
and frame oscillators.
A chain of dividers and appropriate logic circuitry
produce very accurately defined sampling pulses
and the necessary timing signals.
The principal functions implemented are :
- Horizontal scanning processor.
- Frame scanning processor. Two applications are
possible :
- D Class : Po wer stage using an external
thyristor.
- B Class : Power stage using an external power
amplifier with fly-back generator
such as the TDA8170.
- Secondary switch mode power regulation.
The SMPS output synchronize a primary I.C.
(TEA2260/61) at the mains part.
This concept allows ACTIVE STANDBY facilities.
- Dual phase-locked loop horizontal scanning.
- High performance frame and line synchronization
with interlacing control.
- Video identification circuit.
- Super sandcastle.
- AGC key pulse output.
- Automatic 50-60Hz standard identification.
- VCR input for PLL time constant and frame syn-
chro switching.
- Frame saw-tooth generator and phase modula-
tor.
- Switching mode regulated power supply compris-
ing error amplifier and phase modulator.
- Security circuit and start-up processor.
- 500kHz VCO
The circuit is supplied in a 28 pin DIP case.
V
CC
= 12V.
Synchronization Separator
Line synchronization separator
is clamped to
black level of input video signal with synchroniza-
tion pulse bottom level measurement.
The synchronization pulses are divided centrally
between the black level and the synchronization
pulse bottom level, to improve performance on
video signals in noise conditions.
Frame Synchronization
Frame synchronization
is fully integrated (no ex-
ternal capacitor required).
The frame timing identification logic permits auto-
matic adaptation to 50 - 60Hz standards or non-in-
terlaced video.
An automatic synchronization window width sys-
tem provides :
- fast frame capture (6.7ms wide window),
- good noise immunity (0.4ms narrow window).
The internal generator starts the discharge of the
saw-tooth generator capacitor so that it is not dis-
turbed by line fly back effects.
Thanks to the logic control, the beginning of the
charge phase does not depend on any disturbing
effect of the line fly-back.
A32
m
s timing is automatically applied on stan-
dardized transmissions, for perfect interlacing.
In VCR mode, the discharge time is controlled by
an internal monostable independent of the line
frequency and gives a direct frame synchroniza-
tion.
Horizontal Scanning
The horizontalscanning frequency is obtainedfrom
the 500kHz VCO.
The circuit uses two phase-locked loops (PLL) :
the first one controls the frequency, the second one
controls the relative phase of the synchronization
and line fly-back signals.
The frequency PLL has two switched time con-
stants to provide :
- capture with a short time constant,
- good noise immunity after capture with a long
time constant.
The output pulse has a constant duration of 26
m
s,
independent of V
CC
and any delay in switching off
the scanning transistor.
Video Identification
The horizontal synchronization signal is sampled
by a 2
3/9
s pulse within the synchronization pulse.
The signal is integrated by an external capacitor.
The identification function provides three different
levels :
- 0V : no video identification
- 6V : 60Hz video identification
- 12V : 50Hz video identification
This information may be used for timing research
in the case of frequency or voltage synthetizer type
receivers, and for audio muting.
Super Sandcastle
with 3 levels : burst, line fly-
back, frame blanking
In the event of vertical scanning failure, the frame
blanking level goes high to protect the tube.
Frame blanking time (start with reset of Frame
divider) is 24 lines.
VCR Input
This provides for continuous use of the short time
constant of the first phase-locked loop (frequency).
In VCR mode, the frame synchronization window
m
TEA2029C
widens out to a search window and there is no
delay of frame fly-back (direct synchronization).
Frame Scanning
FRAME SAW-TOOTH GENERATOR. The current
to charge the capacitor is automatically switched to
60Hz operation to maintain constant amplitude.
FRAME PHASE MODULATOR (WITH TWO DIF-
FERENTIAL INPUTS). The output signal is a pulse
at the line frequency, pulse width modulated by the
voltage at the differential pre-amplifier input.
This signal is used to control a thyristor which
provides the scanning current to the yoke. The
saw-tooth output is a low impedance, however, and
can therefore be used in class B operation with a
power amplifier circuit.
Switch Mode Power Supply
(SMPS)
Secon-
dary to Primary Regulation
This power supply uses a differential error amplifier
with an internal reference voltage of 1.26V and a
phase modulator operating at the line frequency.
The power transistor is turned off bythe falling edge
of the horizontal saw-tooth.
The ”soft start” device imposes a very small con-
duction angle on starting up, this angle progres-
sively increases to its nominal regulation value.
The maximum conductionangle may be monitored
by forcing a voltage on pin 15. This pin may also
be used for current limitation.
The outputpulse is sent to the primary S.M.P.S. I.C.
(TEA2261) via a low cost synchro transformer.
Security Circuit and Start Up Processor
When the security input (pin 28) is at a voltage
exceeding 1.26V the three outputs are simultane-
ously cut off until this voltage drops below the 1.26V
threshold again. In this case the switch mode
power supply is restarted by the ”soft start” system.
If this cycle is repeated three times, the three
outputs are cut off definitively. To reset the safety
logic circuits, V
CC
must be zero volt.
This circuit eliminates the risk to switch off the TV
receiver in the event of a flash affecting the tube.
On starting up, the horizontal and vertical scanning
functions come into operation at V
CC
= 6V. The
power supply then comes into operation progres-
sively.
On shutting down, the three functions are inter-
rupted simultaneously after the first line fly-back.
ABSOLUTE MAXIMUM RATINGS (limiting values) T
amb
=25
°
C (unless otherwise noted)
Symbol
Parameter
Min.
Max.
Unit
Supply Voltage (pin 8)
14
V
VCC
Operating Supply Voltage (pin 8)
Starting threshold
13.2
V
I
20
AGC Current (pin 20)
5
mA
I
24
Video Identification Current (pin 24)
10
mA
V
12
Negative Line Retrace Voltage (pin 12)
– 20
V
I
12
Line Retrace Current (pin 12)
+ 10
mA
I
10
Line Output Current (pin 10)
– 10
40
mA
I
3
Frame Saw-tooth Generator (pin 3)
20
mA
I
4
Frame Output Current (pin 4)
100
mA
I
7
SMPS Output Current (pin 7)
– 40
40
mA
I
28
Safety Input Current (pin 28)
5
mA
V
28
Safety Input Voltage (pin 28)
V
CC
V
1
/V
2
Common Mode Range (pins 1-2)
10
V
THERMAL DATA
Symbol
Parameter
Value
Unit
R
th (j-a)
Junction-ambient Thermal Resistance
55
°
C/W
ELECTRICAL OPERATING CHARACTERISTICS
T
amb
=25
CV
CC
= 12V (unless otherwise noted) Pulse duration at 50% of the ampl.
Symbol
Parameter
Min. Typ. Max. Unit
I
CC
Supply Current (pin 8, frame, line and SMPS output without load)
50
80 mA
SYNCH SEPARATOR (Pins 26-27)
Positive Video Input AC Coupled (output impedance of signal source < 200
W
)
0.2
1.8
3
V
pp
–I
27
Negative Clamping Current (during synch, pulse)
- 25 - 40 - 55
m
A
I
27
Clamping Current - Pin for slicing level 0.2V < V
27pp
< 2V (50% of sync amplitude) 3
6
9
m
A
4/9
°
TEA2029C
ELECTRICAL OPERATING CHARACTERISTICS
(continued)
Symbol
Parameter
Min.
Typ.
Max. Unit
SYNCH SEPARATOR (Pins 26-27) (continued)
–I
26
Positive Current
0
- 0.75
- 1
nA
A
PULSE FOR KEYED AGC (Pin 20) - Positive (function : without video signal : low level, with video signal : key pulses)
I
20
Negative Current
17
25
36
m
Output Current
5
A
20
Output Saturation Voltage (I
20
= 5 mA)
0.25
0.4
V
t
k
Pulse width (synchro pulse is always inside the key pulse)
6.5
8
8.5
m
s
VCO (Pins 17-18 and 19)
Frequency control range after line divider
(ceramic resonator : 503 kHz)
15.30 to
16.10
kHz
PHASE COMPARATOR
1 (Pin 22)
Output Current Low Loop Gain
j
±
0.35
±
0.50
±
0.65 mA
Output Current High Loop Gain
±
1
±
1.5
±
2A
Window Pulse Width
7
10
13
m
s
VCR SWITCHING (Pin 23)
Threshold Voltage VCR Operating
1.7
2.2
2.7
V
I
23
Input Current (V
23
=0V
CC
= 12V)
- 0.030 - 0.25
- 1
mA
VIDEO IDENTIFICATION (Pin 24)
V
24
Output Saturation Voltage (without video signal, I
24
= 3 mA)
0.2
0.6
V
Output Voltage (with 60 Hz video signal, I
24
= 2.5 mA)
5
6.5
0.6
V
Output Voltage (with 50 Hz video signal, I
24
=10
m
A)
11
11.5
7.5
V
VIDEO IDENTIFICATION (Pin 25)
I
25
Output Current (charging the capacitor)
0.5
0.75
1
mA
t
25
Identification Time (charging the capacitor)
1.3
1.7
2.2
m
s
V
25
Threshold (voltage changing from lower to higher value)
4
4.5
5
V
L
HYS
Hysteresis
150
240
400
mV
H-RAMP GENERATOR (Pin 13)
I
ch13
Charge Current
185
200
215
m
A
V
I13
Base Voltage of Saw-tooth
0.5
V
I
dis13
Discharge Current
3.5
7
mA
SUPER SANDCASTLE (Pin 11)
V
B11
Burst Key Pulse Level Output Voltage (I
11
= - 5mA)
9
V
V
L11
Line Blanking Pulse Level Output Voltage (I
11
= - 5mA)
4
4.5
5
V
V
BT11
Frame Blanking Pulse Level Output Voltage
(and frame out of function) (I
11
= - 5mA)
2
2.5
3
V
T
B11
Delay between Middle of Synch Pulse (pin 27) and Leading
Edge of Burst Key Pulse
2.3
3
m
s
Duration of Burst Key Pulse
3.7
4
5
m
s
T
O11
Delay between SSC Cutting at Pin 12 and Line Blanking Pulse
0.35
m
s
NEGATIVE LINE FLY-BACK INPUT (Pin 12)
Threshold for SMPS Safety
1.1
V
V
bl12
Threshold for Blanking
11
11.5
12
V
V
j
12
Threshold for PLL2
- 1
V
I
12
Input Current 11V < V
12
- 200
m
A
I
12
Input Current 1.3V < V
12
< 11V
-3
3
m
A
I
12
Input Current 0V < V
12
< 1.3V
0
- 80
m
A
I
12
Input Current - 1V < V
12
<0V
0
-1
-2
mA
Line Blanking Trigger
80
m
A
5/9
I
26
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